Bioavailability of once-daily tacrolimus formulations used in clinical practice in the management of De Novo kidney transplant recipients: the better study

Multicenter, prospective, observational study to compare the relative bioavailability of once‐daily tacrolimus formulations in de novo kidney transplant recipients. De novo kidney transplant recipients who started a tacrolimus‐based regimen were included 14 days post‐transplant and followed up for 6 months. Data from 218 participants were evaluated: 129 in the LCPT group (Envarsus) and 89 in the PR‐Tac (Advagraf) group. Patients in the LCPT group exhibited higher relative bioavailability (C_min /total daily dose [TDD]) vs. PR‐Tac (61% increase; P < .001) with similar C_min and 30% lower TDD levels (P < .0001). The incidence of treatment failure was 3.9% in the LCPT group and 9.0% in the PR‐Tac group (P = .117). Study discontinuation rates were 6.2% in the LCPT group and 12.4% in the PR‐Tac group (P = .113). Adverse events, renal function and other complications were comparable between groups. The median accumulated dose of tacrolimus in the LCPT group from day 14 to month 6 was 889 mg. Compared to PR‐Tac, LCPT showed higher relative bioavailability, similar effectiveness at preventing allograft rejection, comparable effect on renal function, safety, adherence, treatment failure and premature discontinuation rates.

Determining the value contribution of emicizumab (Hemlibra®) for the prophylaxis of haemophilia A with inhibitors in Spain by multi-criteria decision analysis

Patients with moderate to severe haemophilia A are at a higher risk of developing FVIII inhibitors that require the use of more costly and less effective treatments. The objective of this study was to determine the value of emicizumab for the prophylaxis of haemophilia A with inhibitors compared to the current therapeutic alternatives, activated prothrombin complex concentrate and recombinant factor VIIa through reflective Multi-Criteria Decision Analysis. The EVIDEM framework adapted to orphan drugs and weighted by a sample of 98 national and regional Spanish evaluators was used. Two structured evidence matrices were developed: emicizumab against activated prothrombin complex concentrate and emicizumab against recombinant factor VIIa. A multidisciplinary team of haemophilia experts rated each of the criteria. Mean and standard deviation were calculated by each criterion and discussed among all participants. Haemophilia A with inhibitors was perceived as a severe disease with high unmet needs. Emicizumab was rated with higher efficacy, therapeutic benefit and quality of life than comparators. When administered alone for the prevention of bleeding events, emicizumab had slightly better safety and tolerability profile than activated prothrombin complex concentrate and similar with recombinant factor VIIa. The inclusion of emicizumab in clinical practice guidelines was valued positively by the members of the panel. Overall, value of emicizumab was higher than activated prothrombin complex concentrate and recombinant factor VIIa, mostly because of efficacy and therapeutic benefit in reducing treated haemorrhages. Reflective Multi-Criteria Decision Analysis has proven to be a feasible method to determine the value contribution of comparative therapies in haemophilia.

Cost-effectiveness of Cladribine Tablets and fingolimod in the treatment of relapsing multiple sclerosis with high disease activity in Spain

OBJECTIVE

To estimate the cost-effectiveness of Cladribine Tablets in the treatment of relapsing multiple sclerosis (RMS) with high disease activity compared with fingolimod, from the perspective of the National Health System (NHS) in Spain.

METHODS

A Markov model was developed. The annual transition probabilities, were adjusted to patients with RMS with high disease activity. The effect of the treatments compared on the Expanded Disability Status Scale (EDSS) was modeled by hazard ratios for the confirmed progression of disability. The annual relapse rate and the probability of suffering adverse reactions were obtained from a meta-analysis and the literature. The derived costs were calculated from Spanish unit costs. The utilities were obtained from the CLARITY clinical trial and the literature. Deterministic and probabilistic sensitivity analyzes were performed.

RESULTS

Cladribine tablets was the dominant treatment: lower costs (-86,536 €) and more effective (+1.11 quality-adjusted life years - QALYs) compared to fingolimod. The probability that Cladribine Tablets was cost-effective compared to fingolimod ranged between 94.6% and 96.1% for willingness to pay from € 20,000 to € 30,000 per QALY gained.

CONCLUSIONS

Cladribine Tablets is a cost-effective treatment, compared to fingolimod, for the treatment of RMS with high disease activity.

EXPERT OPINION

According to the present study, compared to fingolimod, treatment with Cladribine Tablets of relapsing multiple sclerosis with high disease activity is an option that could generate savings for the Spanish National Health System, with a considerable gain in QALYs. Cladribine Tablets is considered cost-effective and dominant (less costs and more effectiveness) than fingolimod treatment option in this population.

Impact of NADPH oxidase functional polymorphisms in acute myeloid leukemia induction chemotherapy

Efficacy and toxicity of anthracycline treatment in acute myeloid leukemia (AML) is mediated by reactive oxygen species (ROS). NADPH oxidase is the major endogenous source of ROS and a key mediator of oxidative cardiac damage. The impact of NADPH oxidase polymorphisms (CYBA:rs4673, NCF4:rs1883112, RAC2:rs13058338) was evaluated in 225 adult de novo AML patients. Variant alleles of NCF4 and RAC2 were related to higher complete remission (P=0.035, P=0.016), and CYBA homozygous variant showed lower overall survival with recessive model (P=0.045). Anthracycline-induced cardiotoxicity was associated to NCF4 homozygous variant (P=0.012) and CYBA heterozygous genotype (P=0.027). Novel associations were found between variant allele of CYBA and lower lung and gastrointestinal toxicities, and a protective effect in nephrotoxicity and RAC2 homozygous variant. Moreover, RAC2 homozygous variant was related to delayed thrombocytopenia recovery. This study supports the interest of NADPH oxidase polymorphisms regarding efficacy and toxicity of AML induction therapy, in a coherent integrated manner.

The view of experts on initiatives to be undertaken to promote equity in the access to orphan drugs and specialised care for rare diseases in Spain: A Delphi consensus

OBJECTIVES

To reach a consensus amongst experts on the most feasible actions to be undertaken to facilitate patient access to specialised care and orphan drugs (OD) in the public health sector in Spain.

METHODS

Two Delphi rounds were completed. The questionnaire was based on a literature review and 2 focus groups. Agreement was sought on the desire (D) and prognosis (P) for the implementation within the next 5 years, on a 5-point Likert scale. Consensus was reached when ≥75% participants chose agreement (1-2) or disagreement options (4-5).

RESULTS

82 experts on rare disease (RD) participated. Agreement on the D and P was reached in 66.07% statements: OD pricing review [absence of clinical effectiveness (D:85.37%; P:85.90%), target population increase (D:79.27%; P:91.03%)]; reference team definition of referral protocols and clinical practice guidelines (D: 97.56%; P: 89.74%); and a unified, usable, etiology-based registry (D:97.56%; P:84.62%). D and P assessment diverged in 32.14% items: creation of a specific funding system for OD (D: 97.56%; P: 60.25%); and a network of medical teams to coordinate the care of RD patients (D: 99%; P: 62%).

CONCLUSIONS

The results have shown the need to promote dialogue between stakeholders, introduce European recommendation to national and regional Spanish policies and set up priorities and undertake actions to drive relevant changes in current medical practice in managing RD patients.

Haemodialysis significantly reduces serum levetiracetam levels inducing epileptic seizures: Case report

WHAT IS KNOWN AND OBJECTIVE

Levetiracetam is used in the treatment of some forms of epilepsy. In renal impairment and patients on chronic haemodialysis, dose adjustment is required. We report a case.

CASE DESCRIPTION

This case report describes a woman on levetiracetam treatment who presented with generalized tonic-clonic seizures during a haemodialysis session. We report on treatment adjustment and on the impact of dialysis on levetiracetam levels.

WHAT IS NEW AND CONCLUSION

Haemodialysis reduces serum levetiracetam concentration and can lead to subtherapeutic levels. Close monitoring is necessary when dialysis is used on patients receiving anticonvulsant drugs that are extensively eliminated by the procedure.

[Risk sharing agreements: with orphan drugs?]

OBJECTIVE

To summarize available information on share risk agreements (RSA) with orphan drugs (OD).

METHODS

A bibliographic search was carried out in MEDLINE, EMBASE and INAHTA using 19 keywords and combinations thereof. Papers published as original, narrative and systematic reviews, editorials, commentaries, letters to the Editor, and special articles were included and reviewed. Public or private institutional reports or documents found in Google that contained relevant information were also reviewed.

RESULTS

experience gained so far with RSA is scant. No published rigorous evaluations of outcomes of these agreements were found. It seems, however, that OD are suitable for introduction in clinical practice by means of RSA. There are two main types of RSA: financially based, and performance-outcome based. A number of theoretical advantages of SRA are described, as well as hurdles that hinder their design, implementation, and followup, and thus endangering their success. Very few RSA have clearly succeed so far.

CONCLUSIONS

If thoroughly managed, RSA may reasonably contribute to value-based pricing of OD, improve their pharmacovigilance, knowledge about their comparative effectiveness, and to reducing uncertainty and its consequences on patients, industry, payers and clinicians. There are technical groups that can bring the essential knowledge to manage RSA in Spain. The challenge now is to be able to harmonize their assessments and appraisals, to put in motion the mechanisms needed to overcome those hurdles, and to provide them adequate political and institutional support.

[Cefditoren pivoxil: A new oral cephalosporin for skin, soft tissue and respiratory tract infections]

Cefditoren pivoxil, a new-third generation cephalosporin antibiotic that has recently been granted approval in Spain, shows important activity over a large part of the pathogens causing skin, soft tissue and respiratory tract infections, including Gram-negative and Gram-positive bacteria. Cefditoren has also been shown to be stable against hydrolysis by many common beta-lactamases. Data from in vitro studies and clinical trials show this antibiotic as an oral formulation with an intrinsic activity against Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pneumoniae equivalent to that of other third-generation cephalosporins administered via parenteral, like cefotaxime or ceftriaxone, thereby placing its maximal benefits mainly in the treatment of ambulatory infections. This paper reviews the main characteristics of cefditoren pivoxil (spectrum of activity, chemical structure, mechanism of action, pharmacokinetics, adverse effects and clinical efficacy) and attempts to find its place in current antibiotic therapeutics.

Phenolic constituents of Phenax angustifolius

Fractionation of an ethanolic extract of the leaves of Phenax angustifolius has resulted in the isolation of two new lignans, 2-hydroxy-2-(3',4'-dihydroxyphenyl)methyl-3-(3' ',4' '-dimethoxyphenyl)methyl-gamma-butyrolactone (1) and 2-hydroxy-2-(4'-O-beta-D-glucopyranosyl-3'-hydroxyphenyl)methyl-3-(3' ',4' '-dimethoxyphenyl)methyl-gamma-butyrolactone (2), and three known compounds, vitexin, isovitexin, and quercetin 3-O-alpha-L-rhamnopyranoside. The structures of 1 and 2 were determined using spectroscopic methods.

Therapeutic drug monitoring of tobramycin: once-daily versus twice-daily dosage schedules

OBJECTIVE

To evaluate the effect of dosage regimen (once-daily vs. twice-daily) of tobramicyn on steady-state serum concentrations and toxicity.

MATERIALS AND METHODS

Patients undergoing treatment with i.v. tobramycin (4 mg/kg/day) were randomised to two groups. Group OD (n = 22) received a once-daily dose of tobramycin and group TD (n = 21) received the same dose divided into two doses daily. Tobramycin serum concentrations (peak and trough) were measured by enzyme multiplied immunoassay. The renal and auditory functions of the patients were monitored before, during and immediately after treatment.

RESULTS

The two groups were comparable with respect to sex, age, body weight and renal function. No statistically significant differences were found in mean daily dose, duration of treatment, or cumulative dose. Trough concentrations were < 2 g/ml in the two groups (100%). Peak concentrations were > 6 microg/ml in 100% of the OD group and in 67% of the TD group (P< 0.01). Mean peak concentrations were markedly different: 11.00+/-2.89 microg/ml in OD vs. 6.53+/-1.45 microg/ml in TD (P< 0.01). The pharmacokinetics parameters were: Ke, (0.15+/-0.03/h in OD vs. 0.24+/-0.06/h in TD), t1/2, (4.95+/-1.41 h in OD vs. 3.07+/-0.71 h in TD), Vd (0.35+/-0.11 l/kg in OD vs. 0.33+/-0.09 l/kg in TD), Cl (0.86+/-0.29 ml/min/kg in OD vs. 1.28+/-0.33 ml/min/kg in TD). Increased serum creatinine was observed in 73% of patients in OD versus 57% of patients in TD, without evidence of nephrotoxicity. In TD group, three patients developed decreased auditory function, of which one presented with an auditory loss of -30 dB, whereas in the OD group only one patient presented decreased auditory function.

CONCLUSION

This small study suggests that a once-daily dosing regimen of tobramycin is at least as effective as and is no more and possibly less toxic than the twice-daily regimen. Using a single-dose therapy, peak concentration determination is not necessary, only trough samples should be monitored to ensure levels below 2 microg/ml.

Selection of optimal prophylactic aminoglycoside dosage in cancer patients: population pharmacokinetic approaches

We report an alternative dose-finding approach for the selection of optimal prophylactic aminoglycoside dosage in specific (sub)populations of patients. Relative a priori utility of several intervals of gentamicin or tobramycin (AMG) peak and trough serum levels were assigned by a group of pharmacokinetics experts, assuming prophylactic administration for laryngectomy interventions. A group of 27 adult patients, with normal renal function, undergoing elective surgery for laryngeal problems and treated prophylactically with gentamicin (80 mg t.i.d.) or tobramycin (100 mg t.i.d.) was studied. Two blood samples (peak and trough) were drawn at steady-state for AMG assay. Three different methods, standard two-stage (STS), extended least-squares non-linear regression [MULTI(ELS)] and non-parametric expected maximization (NEPM), were used to estimate the pharmacokinetic (PK) population parameters. PK simulations were applied to estimate the AMG steady-state concentrations from the PK population parameters. From these data, relative utility values were calculated, allowing the selection of the optimal dosage schedule for this group of patients. There were no statistically significant differences between the PK population estimates as generated by the three methods. Using the STS estimates, the simulation of several dosages indicated that the optimal dosage is 170 mg every 8 h. Conversely, using the individual PK parameters and the mean AMG levels simulated from them, the dose with best relative utility is 130 mg every 8 h. This important difference points out the relevance of the use of relative utilities for the AMG serum concentrations in the selection of optimal a priori dosage. We propose the use of 120 mg every 8 h as the safer dose for our population. Further studies are needed to validate this proposal in patients similar to ours.